Reversible strain-induced magnetic phase transition in a van der Waals magnet

A cryo-strain device capable of applying large, continuous strains to two-dimensional materials in situ enables the reversible tuning of magnetic order and spin-canting process of the layered magnetic semiconductor CrSBr. Mechanical deformation of a crystal can have a profound effect on its physical properties. Notably, even small modifications of bond geometry can completely change the size and sign of magnetic exchange interactions and thus the magnetic ground state. Here we report the strain tuning of the magnetic properties of the A-type layered antiferromagnetic semiconductor CrSBr achieved by designing a strain device that can apply continuous, in situ uniaxial tensile strain to two-dimensional materials, reaching several percent at cryogenic temperatures. Using this apparatus, we realize a reversible strain-induced antiferromagnetic-to-ferromagnetic phase transition at zero magnetic field and strain control of the out-of-plane spin-canting process. First-principles calculations reveal that the tuning of the in-plane lattice constant strongly modifies the interlayer magnetic exchange interaction, which changes sign at the critical strain. Our work creates new opportunities for harnessing the strain control of magnetism and other electronic states in low-dimensional materials and heterostructures.

Automated summary

A cryo-strain device capable of applying large, continuous strains to two-dimensional materials enables the reversible tuning of magnetic order and spin-canting process of the magnetic semiconductor CrSBr.